Benchmark Results: 3D Games
Because Battlefield 3's single-player campaign is so graphics-bound, we don't expect optimizations for processor performance to have much effect. And as suspected, changes attributable to Windows 8 (or even a fully-patched Windows 7) don't yield any benefit.
In contrast to Battlefield 3, the hotfixes for Windows 7 appear to hurt performance in DiRT Showdown, which wasn't around when we took our first look at those Bulldozer architecture-specific operating system updates. Fortunately, Windows 8 ameliorates those issues, yielding just over 4% compared to Windows after a round of automatic updates.
The Elder Scrolls V: Skyrim is sensitive to processor performance. However, Windows 8 doesn't really affect its performance running on AMD's FX-8150.